The Colombia international sustained the problem during Real's 3-0 defeat of Celta Vigo in La Liga on Saturday.

Rodriguez had to be replaced by Alvaro Arbeloa in the 53rd minute and the extent of the injury was revealed on Monday.

"Following tests carried out on James Rodriguez by the Real Madrid Sanitas medical services, he has been diagnosed with a grade one muscular injury in the inner calf of his right leg," a brief statement read.

"His progress will be monitored."

A grade one injury is the least serious of its kind and in the initial statement, Real did not put a timescale on Rodriguez's recovery.

In a press conference ahead of the UEFA Champions League clash with Ludogorets on Tuesday, head coach Carlo Ancelotti said he could possibly feature at the upcoming FIFA Club World Cup.

Real are set to take on the winners of Cruz Azul and Western Sydney Wanderers in the semi-final on December 16, before a potential final four days later.

"James did a test this morning," Ancelotti said. "It showed that it is a very small injury.

"We don't have much time to think about the Club World Cup. He has a slight chance to play in the game on the 20th [should Real progress]."